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Irecently had the pleasure of spending a week with laser scanning and forensic animation expert David Dustin, President of Dustin Forensics and a

member of IAFSM’s Board of Directors (International Associationof Forensic & Security Metrology). The job took us to the island of Guam where we were able to put some of the FARO laser scanning & imaging products, along with the associated software, to use in a customer demonstration.All of the imagery and scans presented here represent mock accident scenes. The equipment that we put to use included a FARO Focus3D X 330 Laser Scanner and the latest FARO Freestyle3D X Handheld Scanner along with FARO’s SCENE Capture the latest revision of FARO’s SCENE software (Version 5.5). Finally, we would like the express our gratitude to the Guam Police Department and the staff of their Crime Laboratory in assisting with the scene set-ups.The mock scene was fi rst scanned with the Freestyle3D X in four scans and in less than 1,000 total frames. As part of the Freestyle3D scanning workfl ow, we incorporated FARO’s photogrammetry targets into the scene. The use of the targets simplifi ed the post-processing effort and allowed us to align each frame in the scan and easily register multiple scans together. The Freestyle3D scans do take slightly more processing time than the Focus3D laser scanning data due to the dense point clouds and larger data fi les, however the workfl ow is quite simple to implement.We then scanned the same scene with the FARO Focus3D X 330 at 1/5 the resolution and 3x the quality. We also used several 80mm Koppa target spheres. These small Koppa spheres are easy to transport and their magnetic mounts allow the user to easily attach them to metallic surfaces such as vehicle doors, or in this case, a riding lawn mower that was set up in the scene. The spheres are also recommended for bullet trajectory analysis. Finally, use of the spheres allows the user to merge Freestyle3D X and Focus3D data scans together since both datasets recognize the spheres, and a standard target registration aligns the scans in a snap. Once the data was processed into two clusters,

we hid the visibility of the Focus3D and Freestyle3D X independently to compare the results. The reader can see the comparison between the Focus3D and Freestyle3D X data in Figures 1 and 2.

Mock Incident Scene Results Using a FARO Freestyle3D with Capture & SCENE SoftwareKelly Watt, Regional Sales Manager – Public Safety Products, FARO Technologies

Figure 1: Mock accident scene data scan comparison (profi le view). Data collect-ed using the FARO Focus3D X 330 appears on the left, and the Freestyle3D X data appears on the right.

Figure 2: Mock accident scene data scan comparison (overhead view). Data collected using the FARO Focus3D X 330 appears on the left, and the Freestyle3D X data appears on the right.

© 2015 FARO Technologies, Inc. All Rights Reserved. This case study is for informational puposes only. FARO makes no warranties–express or implied–in this article FARO, THE MEASURE OF SUCCESS and the FARO Logo are registered trademarks and trademarks of FARO Technologies, Inc.

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Result ComparisonsComparing the results, we see a very clean dataset from the Freestyle3D X. The new Freestyle3D X data had very low-noise and better colorization than previous versions of the Freestyle3D – even comparable to, and slightly better than, the Focus3D in some indoor lighting environments. The unique design of the Freestyle3D X’s dual-infrared color cameras allow the device to collect data from two different angles which delivers clean and accurate data while reducing noise levels (accuracy of 1.5mm and 1mm with the Freestyle3D and Freestyle3D X respectively). Combined with the new visualization tools and best-points fi ltering schemes, we see fantastic scanning results using the product in different applications. Figures 3-5 show several examples of Freestyle3D data scans with and without the new best-point fi ltering.

Some of the recent feature additions for the Freestyle3D, SCENE Capture, and SCENE Version 5.5 include:• Signifi cantly decreased scanning times; prior scans taking 210 seconds have been reduced by 80 seconds

(~ 40% reduction)• Ability to scan point clouds in color or greyscale • New Visualization Tool provides the user with a much more realistic image• One-click auto-leveling allows easier navigation in SCENE• An automatic fl ash mode that activates the built-in LED depending on external lighting conditions; at slow pace

to keep tracking stable and increase performance.• A new best-points fi lter to dramatically reduce noise by fi ltering up to 40% when scanning the same object from

different distances, and removing points from far distances whenever there is a suffi cient point density from a closer distance.

• A printable pdf calibration report• An optional NIST-traceable calibration plate (see Figure 6).

Additionally, the new Freestyle3D X includes an IP52 rating and an accuracy of 1mm.

Figure 4: Stairway scanned using a Freestyle3D. Data without using best-point fi lter (left) and with the fi lter (right).

Figure 5: Carry bag scanned with a Freestyle3D. Data without using best-point fi lter (left) and with the fi lter (right).

Figure 3: Freestyle3D data without using best-point fi lter (left) and with the fi lter (right).

Figure 6: NIST traceable calibration certifi cate